Locking mechanism based on unnatural movement of head-mounted display

ABSTRACT

A wearable computer determines unnatural movements of a head-mounted display (HMD) and triggers a locking mechanism. In one embodiment, the wearable computer receives movement data from one or more sensors and determines that the movement of the HMD is unnatural. In one embodiment, the wearable computer receives movement data from one or more sensors and determines that the HMD is being worn by an unauthorized user. In response to determining an unnatural movement and/or an unauthorized user wearing the HMD, the wearable computer triggers a locking mechanism, which can beneficially provide security measures for the wearable computer.

BACKGROUND

Unless otherwise indicated herein, the materials described in thissection are not prior art to the claims in this application and are notadmitted to be prior art by inclusion in this section.

Numerous technologies can be utilized to display information to a userof a system. Some systems for displaying information may utilize“heads-up” displays. A heads-up display is typically positioned near theuser's eyes to allow the user to view displayed images or information.One type of heads-up display includes a head-mounted display (HMD). Ahead-mounted display can be incorporated into a pair of glasses, ahelmet, or any other item that the user wears on his or her head.

A user may desire the same functionality from an HMD as the user haswith various other systems, such as computers and cellular phones. Forexample, the user may want to have an authentication mechanism for theHMD, such as a password to lock and/or unlock the device.

SUMMARY

In one aspect, a computer-implemented method is provided. The methodinvolves: (1) receiving movement data from at least one sensor of ahead-mounted display (HMD), where the movement data corresponds tomovement of the HMD; (2) determining that the movement data includesdata corresponding to an unnatural movement of the HMD; and in responseto determining that the movement data includes the data pattern, (3)initiating an action that corresponds to the unnatural movement of theHMD.

In another aspect, a wearable-computing system is provided. Thewearable-computing system includes: (1) a non-transitorycomputer-readable medium; (2) program instructions stored on thenon-transitory computer-readable medium and executable by at least oneprocessor to: (a) receive movement data from at least one sensor of ahead-mounted display (HMD), where the movement data corresponds tomovement of the HMD; (b) determine that the movement data includes datacorresponding to an unnatural movement of the HMD; and in response todetermining that the movement data includes data corresponding to theunnatural movement, (c) initiate an action that corresponds to theunnatural movement of the HMD.

In another aspect, a computer-implemented method is provided. The methodinvolves: (1) receiving movement data from at least one sensor of ahead-mounted display (HMD), where the movement data corresponds tomovement of the HMD; (2) determining that the movement data includes adata pattern characteristic of the HMD being worn by an unauthorizeduser, (3) in response to determining that the movement data includes thedata pattern, initiating an action that corresponds to the HMD beingworn by an unauthorized user, wherein the action secures the HMD.

These as well as other aspects, advantages, and alternatives will becomeapparent to those of ordinary skill in the art by reading the followingdetailed description, with reference where appropriate to theaccompanying drawings. Further, it should be understood that thissummary and other descriptions and figures provided herein are intendedto illustrative embodiments by way of example only and, as such, thatnumerous variations are possible. For instance, structural elements andprocess steps can be rearranged, combined, distributed, eliminated, orotherwise changed, while remaining within the scope of the embodimentsas claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a head-mounted display, according to an exemplaryimplementation.

FIG. 2 is a flow chart illustrating a method for initiating an actioncorresponding to an unnatural motion, according to an exemplaryimplementation.

FIG. 3 illustrates an unnatural movement of an HMD, according to anexemplary implementation.

FIG. 4 is a flow chart illustrating a method for initiating an actioncorresponding to the HMD being worn by an unauthorized user, accordingto an exemplary implementation.

FIGS. 5 a and 5 b illustrate the HMD being worn by an unauthorized user,according to exemplary implementations.

FIGS. 6 a and 6 b illustrate the HMD being worn by an unauthorized userrelative to physical objects, according to exemplary implementations.

FIGS. 7 a and 7 b illustrate movements and/or positions of an HMD,according to exemplary implementations.

FIGS. 8 a and 8 b illustrate a wearable computing device that functionsas a head-mounted display, according to exemplary implementations.

FIG. 9 is a functional block diagram of a wearable computing system,according to an exemplary implementation.

DETAILED DESCRIPTION

Exemplary methods and systems are described herein. It should beunderstood that the word “exemplary” is used herein to mean “serving asan example, instance, or illustration.” Any embodiment or featuredescribed herein as “exemplary” is not necessarily to be construed aspreferred or advantageous over other embodiments or features. Theexemplary embodiments described herein are not meant to be limiting. Itwill be readily understood that certain aspects of the disclosed systemsand methods can be arranged and combined in a wide variety of differentconfigurations, all of which are contemplated herein.

A. Overview

Authentication mechanisms to lock and/or unlock devices are generallyprevalent amongst computing devices. Some authentication mechanisms mayinvolve knowledge factors such as usernames, passwords, pass phrases,personal identification numbers, and other possible validatingtechniques. Other authentication mechanisms may involve traits thatuniquely identify a user. For example, a device may unlock aftervalidating an authorized user through fingerprint scanning, retinalpattern recognition, DNA sequences, and/or through other such biometricidentifiers.

The above-mentioned mechanisms are effective for authenticating usersand protecting information after a device has been locked. However, manydevices only lock after a certain period of inactivity (e.g., twominutes), or if a user manually locks the device. Due to the relativesimplicity of such an auto-lock feature (e.g., doing nothing), manyusers choose not to manually lock their devices, and instead rely on theauto-lock feature. In this scenario, there may be a window in time afterthe user ceases to use the device and before the device locksautomatically. This may leave a device unprotected for a given period oftime.

If a device is removed from a user in an undesired manner when it isunlocked (e.g., by a thief), then it is unlikely that the user will havetime to lock their device, which may leave the device may beunprotected. However, it is likely that a user will want to protectinformation when a device is removed in an unintended manner.Accordingly, exemplary methods and systems may involve the recognitionof unnatural movements and/or movements characteristic of unnaturalpositions of the device, which are unlikely to be intended by the user.Upon this recognition, the device may responsively initiate an action torestrict access to the device and/or information stored thereon, such aslocking the device.

In particular, exemplary methods and systems may protect information bydetermining when an unnatural movement of a device occurs and/or amovement characteristic of a device resting in an unnatural position(e.g., a position that is characteristic of use, but is notcharacteristic of use by the device's owner). When such an unnaturalmovement and/or a movement characteristic of unnatural position isdetected, the device may responsively initiate a locking mechanism.

In an exemplary embodiment, a wearable computer that includes ahead-mounted display (HMD) may implement a locking mechanism based on anunnatural movement and/or a movement characteristic of an unnaturalposition. In such an embodiment, the HMD could take the form of orinclude eyeglasses that may be worn by a person, and in particular, byan authorized user of the HMD. Since eyeglasses are typically designedto securely fit a user's face, the eyeglasses may closely follow themovements of the user. In some embodiments, the HMD may be configured toreceive data regarding the user's movements and determine whether anymovements are unnatural. To receive such data, the HMD may include orhave access to movement sensors. The HMD may therefore analyze themovement data in order to determine when an unnatural movement occurs.For example, consider a scenario where a user is wearing the HMD whensuddenly, the HMD is yanked off a user's head. The sensors within theHMD may therefore provide movement data that is indicative of the abruptmovement. In particular, the HMD may include accelerometers configuredto detect the gravitational force associated with the acceleration ofthe yanking movement and determine the unnatural movement. Accordingly,the wearable computer may take actions to prevent use of the device,such as locking itself, setting off an alarm, and/or reporting apossible theft to the owner.

In an exemplary embodiment a wearable computer that includes ahead-mounted display (HMD) may additionally or alternatively implement alocking mechanism based on an unnatural positioning. For example, in anembodiment where the HMD takes the form of glasses, there may be certainpositioning indicators that are associated with how the HMD fits on anauthorized user. Such positioning indicators may include the angle atwhich the HMD sit on the user's head, the pressure exerted against nosepads of the HMD by the user's face, various locations where the user'sfeatures contact the HMD, and so on. Accordingly, the HMD may includepositioning sensors that provide positioning indicators. The HMD maytherefore analyze the positioning indicators in order to determine whenthe HMD is in an unnatural position and responsively lock the HMD.

In some embodiments, an HMD may analyze both movement data andpositioning indicators when determining whether to lock. For example, ifa user is getting too many false positives based on an unnaturalmovement analysis alone (e.g., the device locking when the user does notwant it to), the device may provide a setting to require that both anunnatural movement and an unnatural position indicators be detected,before locking automatically. For example, consider a camera adjoined toor embedded within the HMD. Referring back to the example above, thecamera may obtain a video of the user's face during the removal of theHMD to determine an unnatural movement (possibly capturing footage ofthe HMD being taken off the user.) Then, once the unnatural movement isdetected, the wearable computer may monitor positioning indicators forunnatural positioning.

In response to detecting an unnatural movement, a movementcharacteristic of an unnatural position, and/or an unnatural positioningindicator, the wearable computer may quickly initiate a lockingmechanism. The locking mechanism may prevent access to information inthe glasses by disabling the functionality of the HMD such that noinformation can be viewed or obtained by anyone other than the user. Insome embodiments, the HMD may also trigger an action to inform othersthat the locking mechanism has been initiated. For instance, an HMD maysound an alarm and/or flash lights to alert people in the proximity ofthe device that the HMD is unintentionally removed from the user, oralert authorities such as the police, authorized wearers of the HMD,and/or a private security services.

B. Exemplary Wearable Computer

FIG. 1 is an illustration of a wearable computer, according to anexemplary embodiment. In this example, the wearable computer 102 takeson an eyeglass form. Further, the HMD 102 is worn by a user 100. HMD 102includes lens-frames 104 and 106, a center frame support 108, lenselements 110 and 112, and extending side-arms 114 and 116. Lens elements110 and 112 are configured to be positioned in front of the user's eyes144 and 146, respectively. The center frame support 108 is configured torest the HMD 100 on the user's nose 142. The extending side-arms 114 and116 are configured to secure the HMD 102 to a user's face via user'sears 138 and 140, respectively. The extending side-arms 114 and 116 mayfurther secure the HMD 102 to the user by extending around a rearportion of the user's head. Additionally or alternatively, the wearablecomputing system 100 may be connected to or be integral to ahead-mounted helmet structure. Other possibilities exist as well.

The sensors 118 and 122 are shown mounted on the extending side-arms 114and 116, respectively. However, the sensors 118 and 122 may be providedon other parts of the eyeglasses 102. Although depicted as singlecomponents, the sensors 118 and 122 could include more than one type ofsensor device or element. By way of example and without limitation, thesensors 118 and 122 could be any one or more of a motion detector (e.g.,a gyroscope, an accelerometer, a camera, and/or a shock sensor), animpact sensor, a contact sensor (e.g., capacitive sensing device), alocation determination device (e.g., a GPS device), a magnetometer, andan orientation sensor (e.g., a theodolite). Other sensing devices orelements may be included within the sensors 118 and 122 and othersensing functions may be performed by the sensors 118 and 122.

Camera 120 is shown to be positioned on the extending side-arm 114 ofthe HMD 102; however, the camera 120, or other similar cameras, may beprovided on other parts of the HMD 102. The camera 120 may be configuredto capture images at various resolutions or at different frame rates. Inaddition, camera 120 may also be a video camera directed to captureimages or videos of the wearer. Many video cameras with a small formfactor, such as those used in cell phones or webcams, for example, maybe incorporated into an example of the wearable system 100. AlthoughFIG. 1 illustrates one camera 120, more video cameras may be used, andeach may be configured to capture the same view, or to capture differentviews to obtain information corresponding to the positioning of theglasses 102. For example, the video camera 120 may be forward facing tocapture at least a portion of the real-world view perceived by the user.This forward facing image captured by the video camera 120 may then beused to determine the positioning of glasses 102 with respect to thephysical environment.

C. Exemplary Method for Detecting Unnatural Movements

FIG. 2 is a flow chart illustrating an exemplary method 200. Althoughmethod 200 may be carried out by any number of computing devices orsystems, method 200 is described by way of example as being carried outby a wearable computer, and in particular, by a wearable computer thatincludes or takes the form of an HMD.

As shown in block 202, method 200 involves a wearable computer receivingmovement data, which corresponds to movement of the HMD, from at leastone sensor of an HMD. The wearable computer then determines that themovement data includes data corresponding to an unnatural movement ofthe HMD, as shown by block 204. The unnatural movement may becharacteristic of an unintentional removal of the HMD. In response todetermining that the movement data indicates an unnatural movement, thewearable computer initiates an action that corresponds to the unnaturalmovement, as shown by block 206. Initiating the action may secure theHMD.

i. Receiving Movement Data

As indicated by block 202, exemplary method 200 involves receivingmovement data from at least one sensor of an HMD. Further, the movementdata may correspond to various movements of the HMD. In someembodiments, one or more of the sensors that receive movement data mayinclude gyroscopes, accelerometers, cameras, shock sensors, contactsensors (e.g., capacitive sensing devices), impact sensors, locationdetermination devices (e.g., a GPS device), magnetometers, compasses,sonar devices, and orientation sensors (e.g., a theodolite). Thesesensors may be configured to obtain various types of informationregarding the movement of the HMD. In some embodiments, one or more ofthese sensors may obtain information corresponding to velocity, angularvelocity, and/or acceleration of the HMD. Further, one or more of thesensors may obtain information regarding the direction the HMD isfacing, moving, and/or any changes in direction of the HMD's movement.

ii. Initiating an Action Upon Determining an Unnatural Movement

As indicated by block 206, exemplary method 200 involves initiating aresponsive action when an unnatural movement is detected such that theaction secures the HMD. In an exemplary embodiment, the action maysimply be locking the device, such that a password is required beforeuse of the device can resume. In some embodiments, when an unnaturalmovement is detected, the HMD may go beyond simply locking the device,and prevent access or use of the information within the HMD. Forexample, the HMD may initiate a data encryption process to secureinformation until the HMD is returned to the authorized user. In someembodiments, the HMD may initiate more drastic actions such as erasingdata and/or memory, or even cause itself to self-destruct. Many otherpossibilities may exist.

In some embodiments, the initiated action may vary based on the degreeof unnatural movement that is detected. For example, when movements aredetermined to be slightly unnatural (e.g., slightly exceeding athreshold), a simple authentication mechanism may be required to unlockthe device. For instance, if the user repeatedly moves their head due tohaving the hiccups, the recurring movements may slightly exceed a singlethreshold and cause the HMD to initiate a trivial action such as lockingthe HMD. The locking may require that a user be authenticated through alogin before the HMD unlocks itself. For example, the HMD mayauthenticate the user via use of one or more passwords, pass codes,verification questions, and/or personal identification numbers. Otherpossible authentication methods include, but are not limited to, includefingerprint recognition and/or iris, retinal, and/or pupil scanning.

However, when movements are more unnatural, or in other words, whenmovements provide a stronger indication that measures are necessary tosecure the device (e.g., in the case of theft or attempted theft of theHMD), a more secure authentication mechanism may be required to unlockthe device. For example, a more secure authentication mechanism may berequired when a device detects drastic movements that likely resultedfrom the HMD being yanked off the wearer. As a specific example, a moresecure authentication mechanism may be required when the accelerationand/or the angular velocity greatly exceeds a threshold or exceeds ahigher threshold) and/or when multiple changes in the direction of theHMD occur in a short period of time.

In such embodiments, an authentication mechanism may employ varioustechniques to provide additional security. For example, the HMD maysound an alarm. Further, the HMD may initiate communication to variousgroups and/or individuals. For example, the HMD may notify properauthorities such as police officers, security personnel of a potentialtheft of the HMD, or even other authorized wearers of the HMD (sincethere may be more than one authorized wearer of the HMD.) Further, theHMD may initiate a GPS tracking module in the HMD such that properauthorities, including authorized users, can track the location of theHMD through a personal computing device (i.e. cell phone, laptop, and/ora tablet computer.) Configured as such, a user, service provider, lawenforcement agency, and/or others may be able to locate a lost or stolenHMD. Further, the HMD may require a responsive communication beforeunlocking the device. For instance, the HMD may send an e-mail with apasscode to an e-mail account associated with the authorized user of theHMD. The HMD may then require this passcode be entered before unlockingthe device.

Further, in some embodiments, a police control center or anotherauthority may be notified when an unnatural movement is detected. Insuch an embodiment, the control center may initiate a transfer ofinformation from the HMD to the control center and/or to a securenetwork storage location. Such a control center may be able to takevarious responsive actions and/or may provide an owner of the HMD, aservice provider, a law enforcement agency and/or others with the optionto take various responsive actions. For example, the control center mayerase information on the HMD or provide a user with the option to do so(e.g., via a website, e-mail, or phone call). As another example, thecontrol center may activate a camera adjoined to the HMD to see thereal-world view of the HMD and determine its location and/or theperson(s) possessing the HMD.

In some embodiments, the more drastic actions may be initiated by theHMD regardless of the degree of the unnatural movement. In particular,such drastic actions may be initiated regularly as a matter ofengineering design choice. For example, a user may have extremelyvaluable information in the HMD such that the user may want to have thehighest precautionary measures for detecting unnatural movements andinitiate actions to secure the information. The HMD may be programmed todetect the slightest unnatural movements and responsively lock itself,sound an alarm, notify the police, and disable the HMD.

iii. Determining Unnatural Movements

As indicated by block 204, exemplary method 200 involves determiningthat the movement data includes data corresponding to an unnaturalmovement of the HMD. In some instances, an unnatural movement may becharacteristic of an unintentional removal of the HMD from the wearer.Yet further, a removal of the HMD may be a physical separation betweenthe HMD and the wearer such that the removal is unintended by thewearer. For example, an unintentional removal of the HMD may be causedby another person, an animal, inertia (e.g., being in a car during a caraccident), and/or an object (e.g., a golf ball), which completely knocksthe HMD off of the wearer's face, or caused by something elsealtogether. Further, in certain scenarios, it is also possible that awearer could unintentionally cause their HMD to be removed. For example,the HMD could be jarred loose and fall off the wearer when the wearerinadvertently runs into a physical object. Other examples are alsopossible.

In an exemplary embodiment, an HMD analyzes the movement data receivedin block 202 to detect when an unnatural movement occurs. For example,the HMD may analyze velocity data, angular-velocity data, and/oracceleration data for the HMD in order to determine when an unnaturalmovement occurs. Further, the information regarding the direction theHMD is facing, the direction the HMD is moving (perhaps across differentaxes) or information indicating any change in direction of the HMD'smovement and/or the number of changes in direction of the HMD may alsobe used determine an unnatural movement.

In some embodiments, an HMD may analyze a number of different types ofmovement data to determine when an unnatural movement occurs. Forexample, determining an unnatural movement may involve an analysis ofboth the acceleration and the direction of a movement. More generally,the HMD may analyze various combinations of velocity data,angular-velocity data, directional data indicating the direction the HMDis facing and/or moving, and/or data indicating any change in directionof the HMD across different axes, in order to determine when anunnatural movement occurs. Further, it is also possible that a singletype of movement data may be analyzed separately to determine when anunnatural movement occurs.

In some embodiments, determining an unnatural movement from a particularset of movement data may make it unnecessary to analyze other movementdata. For example, consider a scenario where a user is wearing the HMDwhile driving a car. Suddenly, an object appears in front of the car andthe user is forced to slam on the breaks, causing the car to come to anabrupt stop. As a result, the inertia causes the HMD to fall off theuser, causing it to lose physical contact with the user. The sensorswithin the HMD may provide movement data that is indicative of thesudden change in velocity of the HMD. The data corresponding to thesudden change in velocity (e.g., going from 30 mph to 0 mph in a matterof seconds) may solely indicate an unnatural movement without having toanalyze any other movement data at all. Accordingly, the wearablecomputer may take actions to prevent unauthorized use of the device,such as locking itself.

In some embodiments, an HMD may analyze a combination of different typesof movement data to determine an unnatural movement. For example,consider again the scenario above where the user is wearing the HMDwhile driving a car and the user is forced to slam on the breaks. Ratherthan the change in velocity (i.e. the deceleration from 30 mph to 0 mph)solely indicating an unnatural movement, the HMD may also include acontact sensor to detect an unnatural movement. The contact sensor maybe comprised of a mixed signal programmable device to providecapacitance-based touch sensing and detect the proximity of the userwith respect to the HMD. In particular, some embodiments may include acontact sensor that detects a loss of physical proximity between theuser and the HMD. Further, some embodiments may utilize resistivesensing, surface acoustic wave technology, infrared photo detection,dispersive signal technology, and/or optical imaging to detect theproximity of the user with respect to the HMD. In response to detectingthe deceleration and the distant proximity of the user, the HMD mayinitiate a security mechanism to protect the HMD.

In some embodiments, different combinations of movement data may bepossible to indicate unnatural movements. For example, consider theprevious example where the HMD detects the deceleration and the distantproximity of the user to determine an unnatural movement. However,instead of the contact sensor, the HMD may include an impact sensor toobtain information corresponding to the movement of the HMD. The impactsensor may be configured to determine an angle of deceleration, adirection of an impact, the force of the abrupt stop or crash, and/orany pressure that is applied to the HMD due to inertia. In response todetermining the deceleration and the force of the abrupt stop, the HMDmay trigger a security mechanism to protect information in the HMD.

In some embodiments, determining unnatural movements may involvecomparing the movement data received in block 202 with respectivethresholds. Thresholds may be pre-defined such that exceeding athreshold is indicative of unnatural movement. Further, thresholds maybe defined around typical head movements and/or gestures such as a nodor shaking one's head. For example, a user of an HMD may nod to gestureaffirmatively and the movement associated with a nod may be indicativeof a natural movement. However, a threshold may be pre-defined such thata hard nod (hard enough to remove the HMD from the user's face) wouldindicate an unnatural movement. Accordingly, if movement data indicatesa movement with enough velocity or acceleration to remove the HMD fromthe user's face, the HMD may take actions to lock itself.

In some embodiments, thresholds may be used to determine unnaturalmovements based on a user-profile specifically designed for a user. Theuser-profile may include various characteristics of movements that areunique to the user and numerous thresholds to determine unnaturalmovements. For example, consider the “hard nod” example above but wherethe user attaches an apparatus to the HMD such that extending side-armsof the HMD secure the HMD to the user by extending around a rear portionof the user's head. The hard nod (in the previous example) may no longerbe a movement that would remove the HMD from the user. Therefore, thisuser may update their user-profile such that a hard nod is no longer anunnatural movement. However, the user-profile may include separatethreshold such that an upward movement of the HMD with respect to theuser which may be indicative of an unnatural movement. Numerous otherthresholds may be included in the user-profile to determine unnaturalmovements.

In some embodiments, the user may adjust thresholds such that removingthe HMD from the user's face (and possibly placing the HMD in the user'spocket) is a natural movement. Even though the removal of the HMD may berecognized, it may further be determined that the HMD is still in theuser's possession (or perhaps in the proximity of the user.) Forexample, a capacitance-based touch sensor in the HMD may indicate that aclose physical proximity with the user is sustained. Consequently, nounnatural movements characteristic of an unintentional removal may bedetected and the HMD may not initiate a locking mechanism. In someembodiments, the user may disable all the thresholds such that the HMDmay be physically separated from the user without initiating a securitymechanism. In particular, the user may preconfigure the HMD to disableall thresholds for a period of time. For example, the user may disableall the thresholds in the HMD for a 10-minute time period while the useris taking a shower. Before the 10-minute time period lapses, the usermay have to put the HMD back on the user's face in order to prevent theHMD from initiating a security mechanism to protect itself.

FIG. 3 illustrates an example of unnatural movement of HMD 302 relativeto user 300. The HMD 302 may be the same as, or similar to, HMD 102illustrated in FIG. 1. FIG. 3 is an exemplary illustration of the HMD302 being removed from the user 300. Hereafter referred to as the“thief” example, consider a thief sneaking up behind user 300 and usingtheir left hand 352 to remove HMD 302 from the user 300. The HMD 302 isremoved in an upward direction relative to user 300 and data may beobtained using movement sensors 318 and 322 to determine an unnaturalmovement.

In some embodiments, data from the sensors 318 and 322 may be used todetermine an unnatural movement. Sensors 318 and 322 may be configuredto obtain information corresponding to the velocity, angular velocity,and/or acceleration of the HMD. Further, one or more of the sensors mayobtain information regarding the direction the HMD is facing, moving,and/or any changes in direction of the HMD's movement. For example,sensor 318 may be an accelerometer configured to obtain datacorresponding to the acceleration of the HMD when the HMD 302 isremoved. Further, sensor 320 may be a digital compass configured toobtain data corresponding to the HMD's abrupt changes in direction. Themovement data of the acceleration and the changes in direction of HMD302 may be analyzed in a group to determine an unnatural movement.

In some embodiments, movement data may be compared to various thresholdsto determine an unnatural movement. Referring to the “thief” example,the acceleration data may exceed a certain threshold but may not itselfdetermine an unnatural movement. However, the number of changes in thedirection of the HMD for a given time may also exceed a given threshold.Consequently, exceeding two different thresholds for a single movementmay determine an unnatural movement. Although the movement data fromsensors 318 and 322 may solely be relied upon to determine an unnaturalmovement, images from the camera 320 may also be used.

In some embodiments, camera 320 may capture images to determine anunnatural movement. Further, camera 320 may also be a video cameraobtaining videos to determine an unnatural movement. Camera 320 maycapture images and/or videos of thief's hand 352 removing HMD 302 tointerpret an unintentional removal not caused by user 300 and determinean unnatural movement.

In some embodiments, camera 354 may obtain images and/or videos of theuser's face during the removal to determine an unnatural movementcharacteristic of an unintentional removal. Unlike camera 320, whichfaces outward relative to the user's face, camera 354 may face inwardtowards the user's face such that images and/or videos of a user's facemay be captured to determine unnatural movements. Considering the“thief” example, camera 354 may capture images and/or videos of theuser's ear 338 before the thief's hand 352 removes HMD 302 from user300. During the removal of HMD 302 from the user 300, camera 354 maycapture images and/or videos that are significantly different from theuser's ear 338 (e.g., images of the ground, sky, and/or othersurrounding objects). Consequently, HMD 302 may determine an unnaturalmovement characteristic of an unintentional removal and responsivelyinitiate a locking mechanism to secure itself.

Further, in some embodiments, camera 320 and/or 354 may reveal certaindetails of images taken during a removal of the HMD to determine anunnatural movement. Further, camera 320 and/or 354 may capture imagesreflecting an integration of an environment over periods of exposuredetermined by the shutter speed. In particular, camera 320 and/or 354may capture an image of a scene over a given period of time to determinean unnatural movement characteristic of an unintentional removal. Forexample, considering the previous “thief” scenario, camera 320 and/or354 may capture various details (e.g., motion blur, streaks, and/orsmears) from images taken during the removal of HMD 302 to determine anunnatural movement. Yet further, consider that camera 354 is positionedto capture images of the user's nose 342. During the removal of HMD 302,camera 354 may capture an image of the user's nose 342 withcharacteristics of motion blur due to the movement of the HMD. Theblurred image of user's nose 342 may be analyzed to indicate anunnatural movement of an unintentional removal.

D. Exemplary Methods for Locking Upon Detection of an Unauthorized User

FIG. 4 is a flow chart illustrating an exemplary method 400. Althoughmethod 400 may be carried out by any number of computing devices orsystems, method 400 is described by way of example as being carried outby a wearable computer, and in particular, by a wearable computer thatincludes or takes the form of an HMD.

As shown in block 402, method 400 involves a wearable computer receivingmovement data from at least one sensor of a head-mounted display (HMD),where the movement data corresponds to movement of the HMD. The wearablecomputer then initiates determining that the movement data includes adata pattern characteristic of the HMD being worn by an unauthorizeduser, as shown in block 404. In response to determining that themovement data includes the data pattern, method 400 involves initiatingan action that corresponds to the HMD being worn by an unauthorizeduser, where the action secures the HMD, as shown by block 406. Theaction initiated may secure the HMD; e.g., by locking the HMD and/ortaking other actions.

i. Receiving Data Characteristic of an Unauthorized User

As indicated by block 402, exemplary method 400 involves receivingmovement data from at least one sensor of a head-mounted display (HMD),where the movement data corresponds to movement of the HMD. Further, themovement data may correspond to various movements of the HMDcharacteristic of a user's movements. In some embodiments, one or moreof the sensors that receive movement data and/or patterns of movementsmay include gyroscopes, accelerometers, cameras, shock sensors, contactsensors (e.g., capacitive sensing devices), impact sensors, locationdetermination devices (e.g., a GPS device), magnetometers, compasses,sonar devices, and orientation sensors (e.g., a theodolite). Thesesensors may be configured to obtain various types of informationregarding the movement of the HMD characteristic of a user's movementsand/or patterns of the user's movements. In some embodiments, one ormore of these sensors may obtain information corresponding to velocity,angular velocity, and/or acceleration of the HMD's movement. Further,one or more of the sensors may obtain information regarding thedirection the HMD is facing and/or moving, any changes in direction ofthe HMD's movement, and/or any patterns of the HMD's movement.

In some embodiments, the HMD could take the form of or includeeyeglasses designed to securely fit an authorized user's face andclosely follow the slightest movements of the authorized user.Furthermore, sensors included in the HMD may have varying levels ofsensitivity to detect a range of the HMD's movements. For example, theHMD may include sensors which may be highly sensitive to detect naturalmovements of a user's head while the user is simply wearing the HMD. Thesensors may also capture patterns of natural movements of the user'shead which may correspond to the user's vital characteristics (perhapsrelated to the user's breathing patterns and/or patterns of a user'snatural tremor.) In some embodiments, natural movements and/or patternsof natural movements of the user's head may be unique to every wearer.Further, natural movements and/or patterns of natural movements of theuser's head may be difficult to replicate, and thus may provide a“head-movement fingerprint” that helps identify the authorized owner ofan HMD. In some embodiments, the head-movement fingerprint may bemonitored with other physiological indicators and/or biometric data(possibly using biometric sensors such as pulse sensors to detectpatterns of a user's pulse.)

In some embodiments, the HMD may be configured to receive movement databased on the user speaking, walking, and/or eating while wearing theHMD. However, data related to other day-to-day activities may also bereceived. Similar to the natural movements and/or patterns of naturalmovements described above, movements of the HMD while the user isspeaking, walking, and/or eating may also be unique to each user toprovide a head-movement fingerprint. Further, such a head-movementfingerprint may be provided in a user-profile. For example, the headmovements of a user while the user is speaking may be unique to thisparticular user due to the shape of a user's head and/or jaw structure,body language, and personality (possibly related to a user'sexpressions.) Similar to other uses of the head-movement fingerprint, alocking mechanism may be implemented based when movements of the HMD donot correspond with head movement fingerprint of the owner'suser-profile. In addition, physiological indicators and/or data obtainedfrom biometric sensors may be used in conjunction with the head-movementfingerprint provided in the user-profile to help distinguish anauthorized user from an unauthorized user.

In some embodiments, one or more of the sensors that receive movementdata characteristic of an unauthorized user may include locationdetermination devices (e.g., a GPS device), compasses, sonar devices,orientation sensors (e.g., a theodolite), impact sensors, and/or contactsensors (e.g., capacitive sensing devices.) These sensors may beconfigured to obtain various types of information regarding the movementof an HMD characteristic of an unnatural position. In some embodiments,one or more of these sensors may obtain information corresponding to thedirection the HMD is facing, any pressure exerted on parts of the HMD,and/or the position of the HMD with respect to the wearer.

In some embodiments, one or more sensors may obtain various types ofinformation to create a user-profile unique to a user. For example, oneor more sensors may obtain characteristics of a user wearing the HMD,which may be custom-fitted for the user. In some embodiments, thesecharacteristics may include the distance between the HMD and the user'sface, an angle of the HMD relative to the wearer, and/or a rotation ofthe HMD relative to a visual plane on the user. In addition, anexemplary embodiment may have thresholds corresponding to the yaw,pitch, and azimuth of the HMD while worn by the user. The action takento secure the HMD may vary according to which threshold or thresholdsare exceeded. Furthermore, one or more sensors may capture normal and/orfrequently-held positions of the HMD (possibly incorporating a user'shabits) to be reflected in the user-profile. For example, a user mayhave a chronic neck problem and the user may routinely stretch theirneck to place the HMD at an angle for several minutes during a stretch.This may be reflected in the user-profile as a normal positioncharacteristic of the stretch.

ii. Initiating an Action Upon Determining an Unauthorized User

As indicated by block 406, exemplary method 400 involves initiating aresponsive action that corresponds to the HMD being worn by anunauthorized user, where the action secures the HMD.

In some embodiments, the responsive action may vary depending on thedata pattern characteristic of the HMD being worn by an unauthorizeduser. For example, consider that a user's natural movementscorresponding to the user's vital characteristics do not fully match ahead-movement finger print in the owner's user-profile. In particular,contemplate that the user's natural tremors do not match with thenatural movement patterns in the owner's user-profile. The HMD mayinitiate an authentication mechanism such as locking the HMD. Thelocking may require the user to be authenticated through iris-scanningsuch that the user can unlock the device and begin operating it again.In a similar example, the HMD may slightly exceed a single thresholdmeasuring the distance between the HMD and a user according to theowner's user-profile. Similarly, this measurement may result in anaction for the HMD to lock itself and simply prompt the wearer for apassword to unlock the device. However, in a different example, a thiefmay attempt to steal the HMD from the wearer by grabbing the HMD. Thismovement may exceed thresholds corresponding to both an angle of the HMDrelative to the wearer and a rotation of the HMD relative to a visualplane of the wearer. Both thresholds may be exceeded by large margins tocause the HMD to lock itself, sound an alarm, and notify the policeregarding the location of the HMD.

iii. Determining an Unauthorized User

As indicated by block 404, exemplary method 400 involves determiningthat the movement data includes a data pattern characteristic of the HMDbeing worn by an unauthorized user.

In some embodiments, natural movements and/or patterns of naturalmovements may be used to determine an unauthorized user. For example,consider an owner of an HMD whose patterns of natural movements may bedifficult or nearly impossible to replicate such that a head movementfingerprint is created for the owner's user-profile. Yet further, theuser-profile may be used to authenticate the owner when a user simplywears the HMD for a short period of time (i.e. less than fifteenseconds.) For instance, an owner's natural movement corresponding totheir breathing pattern may be captured in a user-profile for the owner.When an unauthorized user wears the HMD, a comparison may be madebetween the unauthorized user's movements due to their breathing patternversus movements indicated in the head movement fingerprint captured inthe user-profile for the owner. Since the head movement fingerprint isnot detected when the HMD is worn by the unauthorized user, the HMD maylock itself and prompt the user with an authentication login.

In some embodiments, an unauthorized user may be determined based on amovement characteristic of an abnormal position of the HMD. In certainscenarios, it is also possible that a user could unintentionally causetheir HMD to be put in an abnormal position. For example, a user maysneeze and while simultaneously moving to cover their mouth, they mayinadvertently knock the HMD off the user's face, placing the HMD in anabnormal position characteristic of a removal of the HMD. This may causethe HMD to lock itself. Other examples are also possible.

In an exemplary embodiment, an HMD may analyze the data received todetect when the HMD is in an abnormal position characteristic of beingworn by an unauthorized user. For example, the HMD may analyze thedirection the HMD is facing, the orientation of the HMD with respect tothe wearer, and/or changes in the balance of the HMD. Further,information regarding a distance between the HMD and a wearer of theHMD, an angle of the HMD relative to the wearer, and a rotation of theHMD relative to an imaginary visual plane of the HMD may also be used todetermine an abnormal position. For example, consider that the userslowly removes the HMD and gradually turns it upside down. The HMD mayanalyze the movement data based on gravity to detect an abnormalposition and disable the device.

In some embodiments, a user-profile including positioningcharacteristics may also be used determine an abnormal positioncharacteristic of being worn by an unauthorized user. A user-profile mayinclude various positioning characteristics corresponding to a naturalposition of an authorized user. For example, a positioningcharacteristic of a user-profile may include the distance between a lensof the HMD and the user's face while comfortably wearing the HMD.Further, consider a sonar sensor in the HMD configured to measure thisdistance (perhaps through sampling continuously or periodically) whilethe user is wearing the HMD. A comparison can be made between thedistance in the positioning characteristic versus the distance measuredby the sonar sensor. If the sonar sensor obtains a distance that exceedsthe distance in the user-profile (by a pre-determined margin orthreshold), an unauthorized user may be detected.

In some embodiments, determining whether the HMD is likely being worn byanother person includes detecting an abnormal position. For example,consider an unknown user (e.g., an unauthorized user) wearing an HMDbelonging to an authorized user. A gyroscope in the HMD may obtain anangle of the HMD's orientation with respect to the unauthorized user anddetermine that the HMD is rotated compared to a normal position includedin the user-profile (which is designed for the authorized user.)Further, the rotated position of the HMD may exceed an angle in theuser-profile by a pre-determined margin to determine an abnormalposition. Yet further, the rotated position of the HMD may be held pasta period of time allowable by another threshold. Exceeding this timelimit may determine an abnormal position. Other possibilities may alsoexist.

In some embodiments, one or more sensors may obtain data correspondingto an orientation of the HMD relative to the following: (a) a physicalenvironment of the HMD; (b) a physical object having a known physicallocation; and (c) a user who is wearing the HMD. For example, consider acamera proximate to the HMD that may periodically capture images of theuser's nose. A comparison may be made between the images of the user'snose and the user's nose characterized in the user-profile. Thiscomparison may be made periodically (possibly using various samplingrates of the camera) to determine that the HMD is in a normal position.Referring back to the example of the “unknown user” above, the cameramay intermittently capture images of the unknown user's nose todetermine that the images differ substantially from the user's noseidentified as a positioning characteristic of the user-profile.Accordingly, an abnormal position may be determined and the HMD maydisable itself.

FIGS. 5 a and 5 b illustrate the HMD being worn by an unauthorized user,according to an exemplary implementation. HMD 502 in FIGS. 5 a and 5 bmay be the same as, or similar to, HMD 302 illustrated in FIG. 3 and HMD102 illustrated in FIG. 1. FIG. 5 a is an exemplary illustration of HMD502 being worn by an authorized user 500 a and FIG. 5 b illustrates HMD502 being worn by an unauthorized user, 500 b. HMD 502 may becustom-designed to fit user 500 a and user-profile may be created forHMD 502 fitting user 500 a.

In some embodiments, a visual plane of the HMD may be included as apositioning characteristic in a user-profile to determine normalpositions of the HMD when worn by an authorized user. For example,consider FIG. 5 a where horizontal plane 546 of HMD 502 may be includedas a positioning characteristic in the user-profile for user 500 a. Inaddition, vertical plane 550 may also be included as a positioningcharacteristic in the user-profile. Both horizontal plane 546 andvertical plane 550 may indicate normal positions of the HMD 502 withrespect to user 500 a. In some embodiments, motion sensors and positionsensors may provide data for determining actual planes of the HMD. Forexample, sensors 518 and 522 may include gyroscopes, accelerometers,location determination devices (e.g., a GPS device), magnetometers,orientation sensors (e.g., a theodolite), sonar devices, compasses,contact sensors (e.g., capacitive sensing device), impact sensors,and/or other position sensors configured to obtain actual visual planesof the HMD 502 with respect to a user. Camera 520 may also be used aswell to determine actual planes. Yet further, camera 520 and sensors 518and 522 may obtain data individually and/or obtain data collectively todetermine actual planes. Other possibilities may exist.

In some embodiments, a positioning characteristic in a defaultuser-profile may be used to determine when an abnormal position issubstantially different from at least one natural positioncharacteristic of a movement of the HMD. In particular of theseembodiments, actual planes (possibly defined as positioningcharacteristics) may be compared with planes included in user-profilesto determine abnormal positions. For example, when HMD 502 are worn byuser 500 a, actual horizontal plane 544 and vertical plane 548 alignswith horizontal plane 546 and vertical plane 550 included in the defaultuser-profile, respectively. Therefore, a normal position is determinedin FIG. 5 a. However, when HMD 502 are worn by user 500 b as shown inFIG. 5 b, horizontal plane 544 does not align with horizontal plane 546defined in the default user-profile. Similarly, vertical plane 548 doesnot align with vertical plane 550. Yet further, the misalignments mayexceed a certain threshold defined as a positioning characteristicincluded in the default user-profile to indicate a substantiallydifferent position. For example, consider a default user-profileincluding a positioning characteristic such that angle 552 has athreshold of 5 degrees (as shown in FIG. 5 b.) Since angle 552 mayexceed the threshold of 5 degrees when HMD 502 is worn by user 500 b, anabnormal position substantially different from a normal position may bedetermined. In some embodiments, the misalignments may be held for aperiod of time exceeding certain thresholds of time also indicated inthe user-profile. Considering the previous example, the threshold of 5degrees may need to be exceeded for 5 consecutive minutes to indicate asubstantially different position. In response to determining an abnormalposition substantially different from a normal position as described inany of the examples above, HMD 502 may initiate a security mechanism toinform security personnel that the HMD 502 are not worn by an authorizeduser.

In some embodiments, substantially different positions may be determinedby a default user profile created based on average and/or typicalmovements of a human's head and/or body. For example, considering FIG.5, a default user-profile for user 500 a may include a threshold of 5degrees for angle 552 based on average human movements and/or thresholdstypically used. In some embodiments, a substantially different positionmay be determined by a user-profile custom-designed for a certain user.For example, consider a user-profile custom-designed for user 500 awhich includes a threshold indicating a position that is substantiallydifferent when angle 552 is greater than or equal to 3 degrees. When theHMD rotates such that angle 552 is greater than or equal to 3 degrees,the HMD may determine a substantially different position and initiate alocking mechanism to prompt the user with an authentication login. Insome embodiments, angle 552 may be adjusted by the user to define aposition that is substantially different. For example, the threshold forangle 552 may be adjusted to 1 degree (possibly by the user) to indicatea position that is substantially different from a normal position.

In some embodiments, a positioning characteristic in a user-profile maybe disabled to prevent the determination of an abnormal position that issubstantially different from a normal position. For example, consideringthe scenario above, the user may disable the positioning characteristicfor angle 552 such that HMD 502 may rotate beyond the threshold of 3degrees. Furthermore, other positioning characteristics in auser-profile may be disabled such that HMD 502 can be worn by user 500 bwithout indicating a substantially different position.

E. Determining an Unauthorized User Relative to Physical Objects

FIGS. 6 a and 6 b illustrate an unauthorized user of an HMD relative tophysical objects, according to an exemplary implementation. HMD 602 inFIGS. 6 a and 6 b may be the same or similar to HMD 502 illustrated inFIGS. 5 a and 5 b. In addition, user 600 a and 600 b may be the same asor similar to users as 500 a and 500 b, respectively. HMD 602 may becustom-designed to fit user 600 a.

In some embodiments, abnormal positions may be determined with the useof a camera capturing the orientation of an HMD with respect to physicalobjects. For example, FIG. 6 a illustrates HMD 602 being worn by a user600 a and FIG. 6 b illustrates HMD 602 being worn by a different user,600 b. FIGS. 6 a and 6 b illustrate two different positions of the HMD602 with respect to two different users. In addition, FIGS. 6 a and 6 bshow differences between images 659 and 660 captured by a camera 620during two different instances. (FIG. 6 a illustrates image 659 taken bycamera 620 when HMD 602 is worn by user 600 a and FIG. 6 b shows image660 taken by camera 620 when HMD 602 is worn by user 600 b.) It may bedetermined that the differences between image 659 and 660, namely theorientation of HMD 602 with respect to laptop 654 and cell phone 655, isa result of an abnormal position. This determination may initiate anaction to lock HMD 602 such that user 600 b is unable to access HMD 602.

For example, consider a scenario in FIG. 6 a where the user 600 a issitting at a desk in their office wearing HMD 602 in front of user 600a's laptop computer 654 and cell phone 655. The camera 620 captures animage 659 of the laptop computer 654 and cell phone 655. Subsequently,user 600 a leaves the office whereupon user 600 a is followed by user600 b. Consider that user 600 b is a spy trying to obtain informationfrom laptop computer 654. Therefore, contemplate that user 600 b sneaksbehind user 600 a, removes HMD 602 from user 600 a, and sedates user 600a to successfully obtain possession HMD 602. In some embodiments,sensors 618 and 622 may obtain movement data that determines an abnormalmovement of the HMD 602, which may be a characteristic of anunintentional removal of HMD 602. In some embodiments, sensors 618 and622 may obtain position data that determines a position of HMD 602 thatis substantially different from at least one normal position of the HMD,where the normal positions may be indicated by a user-profile for user600 a. In some embodiments, the abnormal position may be characteristicof an unintentional removal of the HMD from a wearer.

However, for the purposes of illustration, consider the example abovewhile ignoring any abnormal movement or position that may be detectedwhen user 600 b obtains possession of HMD 602. Instead, contemplate thatuser 600 b, while wearing HMD 602, returns to the desk in the officewhere user 600 a was previously wearing HMD 602. User 600 b, whiletrying to obtain information from laptop computer 654, looks in the samedirection that user 600 a was looking previously. Therefore, camera 620is situated to capture image 660 which includes laptop computer 654 andcell phone 655 (similar to when image 659 was taken when HMD 602 wasworn by user 600 a.) However, user 600 b may have physicalcharacteristics that differ from user 600 a (e.g., user 600 b may betaller than user 600 a.) Further, user 600 b may have a different facialand/or head structure than user 600 a such that the position of the HMD602 rotates slightly as shown in FIG. 6 b (possibly similar to theillustration of HMD 502 in FIG. 5 b compared to FIG. 5 a.) It may berecognized that laptop 654 has shifted from its original position 657 bythe same degree that cell phone 655 has shifted from its originalposition 658. Since both laptop 654 and cell phone 655 have movedtogether and by the same (or similar) angle, it may be determined thatneither laptop 654 nor cell phone 655 have moved independently. Instead,it may be determined that there has been a change in an orientation ofHMD 602 with respect to physical objects in the vicinity. Recognizingthis change, an abnormal position of HMD 602 may be determined. In someembodiments, the change in orientation may exceed a time periodpre-defined in a user-profile for user 600 a to determine an abnormalposition. In some embodiments, the position of HMD 602 may besubstantially different from at least one normal position of the HMD,where the normal positions may be indicated by a user-profile for user600 a. In some embodiments, the abnormal position may be characteristicof an unintentional removal of the HMD from a wearer.

It should be understood that the camera 620 may capture images of otherobjects in the physical environment proximate to the user 600 todetermine the orientation or changes in the orientation of surroundingobjects. For example, the camera 620 may be positioned in other regionsof the HMD 602 to capture different images. In some embodiments, camera620 may be positioned such that it captures images of the user's face.In addition, camera 620 may be positioned to capture images of otherpeople proximate to the user. In some embodiments, HMD 602 may havemultiple cameras capturing various images of the physical environmentproximate to the user.

F. Movements and/or Positions of an HMD

FIGS. 7 a and 7 b illustrate movements and/or positions characteristicof movements of an HMD, according to exemplary implementations. Further,HMD 702 may include an HMD worn by user 700. In FIG. 7 a, HMD 702 ismoved to position 702 a such that lens elements 710 and 712 are raisedabove a normal position of the HMD whereas extending side-arm 114 pivotsbehind the user's ear 738. Sensor 718 may determine this movement to bea typical movement. In addition, camera 720 may capture images todetermine that the position of the HMD is in a normal position.Furthermore, camera 720 may capture images determining that position 702a has equivalent or close positioning characteristics as what isprovided in the user-profile indicating a normal position. For example,camera 720 may capture that extending side-arm 714 is within apre-defined distance from the user's ear 738 to determine that HMD 702is in a normal position. In some embodiments, this position may be heldindefinitely without determining an abnormal position.

In FIG. 7 b, extending side-arm 714 is raised above the user's ear 738.In some embodiments, sensor 718 may determine this movement to be anormal movement. However, camera 720 may capture images indicating anabnormal position. Referring back to the example above, the pre-definedthe distance between side-arm 714 and user's ear 738 may be exceeded.Therefore, although a normal movement may be determined, it may bedetermined that position 702 b is an abnormal position. Furthermore, theHMD 702 may initiate a locking mechanism. Other possibilities andcombinations may exist.

H. Exemplary Wearable Computing Device

In accordance with an example embodiment, a wearable computing systemmay comprise various components, including one or more processors, oneor more forms of memory, one or more sensor devices, one or more I/Odevices, one or more communication devices and interfaces, and ahead-mounted display (HMD), all collectively arranged in a manner tomake the system wearable by a user. The wearable computing system mayalso include machine-language logic (e.g., software, firmware, and/orhardware instructions) stored in one or another form of memory andexecutable by one or another processor of the system in order toimplement one or more programs, tasks, applications, or the like. Thewearable computing system may be configured in various form factors,including, without limitation, integrated in the HMD as a unifiedpackage, or distributed, with one or more elements integrated in the HMDand one or more others separately wearable (e.g., as a garment, in agarment pocket, as jewelry, etc.).

Although described above as a component of a wearable computing system,it is sometimes convenient to consider an HMD to be (or at least torepresent) the wearable computing system. Accordingly, unless otherwisespecified, the terms “wearable head-mounted display” (or “wearable HMD”)or just “head-mounted display” (or “HMD”) will be used herein to referto a wearable computing system, in either an integrated (unifiedpackage) form, a distributed (or partially distributed) form, or otherwearable form.

FIG. 8 a illustrates an example wearable computing system 800 forreceiving, transmitting, and displaying data. In accordance with anexample embodiment, the wearable computing system 800 is depicted as awearable HMD taking the form of HMD 802. However, it will be appreciatedthat other types of wearable computing devices could additionally oralternatively be used.

As illustrated in FIG. 8 a, the HMD 802 comprise frame elementsincluding lens-frames 804 and 806 and a center frame support 808, lenselements 810 and 812, and extending side-arms 814 and 816. The centerframe support 808 and the extending side-arms 814 and 816 are configuredto secure the HMD 802 to a user's face via a user's nose and ears,respectively. Each of the frame elements 804, 806, and 808 and theextending side-arms 814 and 816 may be formed of a solid structure ofplastic or metal, or may be formed of a hollow structure of similarmaterial so as to allow wiring and component interconnects to beinternally routed through the HMD 802. Each of the lens elements 810 and812 may include a material on which an image or graphic can bedisplayed. Each of the lens elements 810 and 812 may also besufficiently transparent to allow a user to see through the lenselement. These two features of the lens elements could be combined; forexample, to provide an augmented reality or heads-up display where theprojected image or graphic can be superimposed over or provided inconjunction with a real-world view as perceived by the user through thelens elements.

The extending side-arms 814 and 816 are each projections that extendaway from the frame elements 804 and 806, respectively, and arepositioned behind a user's ears to secure the HMD 802 to the user. Theextending side-arms 814 and 816 may further secure the HMD 802 to theuser by extending around a rear portion of the user's head. Additionallyor alternatively, the wearable computing system 800 may be connected toor be integral to a head-mounted helmet structure. Other possibilitiesexist as well.

The wearable computing system 800 may also include an on-board computingsystem 818, a video camera 820, a sensor 822, a finger-operable touchpad 824, and a communication interface 826. The on-board computingsystem 818 is shown to be positioned on the extending side-arm 814 ofthe HMD 802; however, the on-board computing system 818 may be providedon other parts of the HMD 802. The on-board computing system 818 mayinclude a one or more processors and one or more forms of memory, forexample. One or more processors may execute instructions stored on someform of non-transitory tangible computer readable storage medium, suchas magnetic or optical disk, or the like, and provided for transfer tothe wearable head-mounted display's memory during configuration or otherprocedure(s). The on-board computing system 818 may be configured toreceive and analyze data from the video camera 820, the finger-operabletouch pad 824, and the wireless communication interface 826 (andpossibly from other sensory devices, user interfaces, or both) andgenerate images for output to the lens elements 810 and 812.

The video camera 820 is shown to be positioned on the extending side-arm814 of the HMD 802; however, the video camera 820 may be provided onother parts of the HMD 802. The video camera 820 may be configured tocapture images at various resolutions or at different frame rates. Manyvideo cameras with a small form factor, such as those used in cellphones or webcams, for example, may be incorporated into an example ofthe wearable system 800. Although FIG. 8 a illustrates one video camera820, more video cameras may be used, and each may be configured tocapture the same view, or to capture different views. For example, thevideo camera 820 may be forward facing to capture at least a portion ofthe real-world view perceived by the user. This forward facing imagecaptured by the video camera 820 may then be used to generate anaugmented reality where computer generated images appear to interactwith the real-world view perceived by the user.

The sensor 822 is shown mounted on the extending side-arm 816 of the HMD802; however, the sensor 822 may be provided on other parts of the HMD802. Although depicted as a single component, the sensor 822 in FIG. 8 acould include more than one type of sensor device or element. By way ofexample and without limitation, the sensor 822 could be any one or moreof a motion detector (e.g., a gyroscope and/or an accelerometer), alocation determination device (e.g., a GPS device), a magnetometer, andan orientation sensor (e.g., a theodolite). Other sensing devices orelements may be included within the sensor 822 and other sensingfunctions may be performed by the sensor 822.

The finger-operable touch pad 824, shown mounted on the extendingside-arm 814 of the HMD 802, may be used by a user to input commands.The finger-operable touch pad 824 may sense at least one of a positionand a movement of a finger via capacitive sensing, resistance sensing,or a surface acoustic wave process, among other possibilities. Thefinger-operable touch pad 824 may be capable of sensing finger movementin a direction parallel to the pad surface, in a direction normal to thepad surface, or both, and may also be capable of sensing a level ofpressure applied. The finger-operable touch pad 824 may be formed of oneor more translucent or transparent insulating layers and one or moretranslucent or transparent conducting layers. Edges of thefinger-operable touch pad 824 may be formed to have a raised, indented,or roughened surface, so as to provide tactile feedback to a user whenthe user's finger reaches the edge of the finger-operable touch pad 824.Although not shown in FIG. 8 a, the HMD 802 could include one moreadditional the finger-operable touch pads, for example attached to theextending side-arm 816, and could be operated independently of thefinger-operable touch pad 824 to provide a duplicate and/or differentfunction.

The communication interface 826 could include an antenna and transceiverdevice for support of wireline and/or wireless communications betweenthe wearable computing system 800 and a remote device or communicationnetwork. For instance, the communication interface 826 could supportwireless communications with any or all of 3G and/or 4G cellular radiotechnologies (e.g., CDMA, EVDO, GSM, UMTS, LTE, WiMAX), as well aswireless area network technologies such as a Bluetooth and WiFi (e.g.,802.11a, 802.11b, 802.11g). Other types of wireless access technologiescould be supported as well. The communication interface 826 could enablecommunications between the wearable computing system 800 and one or moreend devices, such as another wireless communication device (e.g., acellular phone or another wearable computing device), a user at acomputer in a communication network, or a server or server system in acommunication network. The communication interface 826 could alsosupport wired access communications with Ethernet or USB connections,for example.

FIG. 8 b illustrates another view of the wearable computing system 800of FIG. 8 a. As shown in FIG. 8 b, the lens elements 810 and 812 may actas display elements. The HMD 802 may include a first projector 828coupled to an inside surface of the extending side-arm 816 andconfigured to project a display image 832 onto an inside surface of thelens element 812. Additionally or alternatively, a second projector 830may be coupled to an inside surface of the extending side-arm 814 andconfigured to project a display image 834 onto an inside surface of thelens element 810.

The lens elements 810 and 812 may act as a combiner in a lightprojection system and may include a coating that reflects the lightprojected onto them from the projectors 828 and 830. In someembodiments, a special coating may not be used (e.g., when theprojectors 828 and 830 are scanning laser devices).

Since the lens elements 810 and 812 are transparent, a forward viewingfield may be seen concurrently with projected or displayed images (suchas display images 832 and 834). This is represent in FIG. 8 b by thefield of view (FOV) object 836-L in the left lens element 812 and thesame FOV object 836-R in the right lens element 810. The combination ofdisplayed images and real objects observed in the FOV may be one aspectof augmented reality, referenced above.

In alternative embodiments, other types of display elements may also beused. For example, the lens elements 810, 812 themselves may include: atransparent or semi-transparent matrix display, such as anelectroluminescent display or a liquid crystal display; one or morewaveguides for delivering an image to the user's eyes; and/or otheroptical elements capable of delivering an in focus near-to-eye image tothe user. A corresponding display driver may be disposed within theframe elements 804 and 806 for driving such a matrix display.Alternatively or additionally, a scanning laser device, such aslow-power laser or LED source and accompanying scanning system, can drawa raster display directly onto the retina of one or more of the user'seyes. The user can then perceive the raster display based on the lightreaching the retina.

Although not shown in FIGS. 8 a and 8 b, the wearable system 800 canalso include one or more components for audio output. For example,wearable computing system 800 can be equipped with speaker(s),earphone(s), and/or earphone jack(s). Other possibilities exist as well.

While the wearable computing system 800 of the example embodimentillustrated in FIGS. 8 a and 8 b is configured as a unified package,integrated in the HMD component, other configurations are possible aswell. For example, although not explicitly shown in FIGS. 8 a and 8 b,the computing system 800 could be implemented in a distributedarchitecture in which all or part of the on-board computing system 818configured remotely from the HMD 802 and made wearable in or on clothingas an accessory (e.g., in a garment pocket or on a belt clip).Similarly, various other (though not necessarily all other) componentsdepicted in FIGS. 8 a and/or 8 b as integrated in the HMD 802 could alsobe configured remotely from the HMD component. In such a distributedarchitecture, certain components might still be integrated in HMDcomponent. For instance, several of the one or more sensors (e.g., anaccelerometer and/or an orientation sensor) could be integrated in HMD802.

In an example distributed configuration, the HMD component (includingother integrated components) could communicate with remote componentsover via the communication interface 826 (or via a dedicated connection,distinct from the communication interface 826). By way of example, awired (e.g. USB or Ethernet) or wireless (e.g., WiFi or Bluetooth)connection could support communications between a remote computingsystem and a HMD component. Additionally, such a communication linkcould be implemented between a HMD component and other remote devices,such as a laptop computer or a mobile telephone, for instance.

FIG. 9 is a block diagram depicting functional components of an examplewearable computing system 902 in accordance with an example embodiment.As shown in FIG. 9, the example wearable computing system 902 includesone or more processing units 904, data storage 906, transceivers 912,communication interfaces 914, user I/O devices 916, and sensor devices928, all of which may be coupled together by a system bus 938 or othercommunicative interconnection means. These components may be arranged tosupport operation in accordance with an example embodiment of a wearablecomputing system, such as system 100 shown in FIGS. 1 a and 1 b, orother a wearable HMD.

The one or more processing units 904 could include one or moregeneral-purpose processors (e.g., microprocessors) and/or one or morespecial-purpose processors (e.g., dedicated digital signal processor,application specific integrated circuit, etc.). In turn, the datastorage 906 could include one or more volatile and/or non-volatilestorage components, such as magnetic or optical memory or disk storage.Data storage 906 can be integrated in whole or in part with processingunit 904, as cache memory or registers for instance. As further shown,data storage 906 is equipped to hold program logic 908 and program data910.

Program logic 908 could include machine language instructions (e.g.,software code, firmware code, etc.) that define routines executable bythe one or more processing units 904 to carry out various functionsdescribed herein. Program data 910 could contain data used ormanipulated by one or more applications or programs executable by theone or more processors. Such data can include, among other forms ofdata, program-specific data, user data, input/output data, sensor data,or other data and information received, stored, retrieved, transmitted,analyzed, or modified in the course of execution of one or more programsor applications.

The transceivers 912 and communication interfaces 914 may be configuredto support communication between the wearable computing system 902 andone or more end devices, such as another wireless communication device(e.g., a cellular phone or another wearable computing device), a user ata computer in a communication network, or a server or server system in acommunication network. The transceivers 912 may be coupled with one ormore antennas to enable wireless communications such those describeabove in connection with the wireless communication interface 826 shownin FIG. 8 a. The transceivers 912 may also be coupled with one or moreand wireline connectors for wireline communications such as Ethernet orUSB. The transceivers 912 and communication interfaces 914 could also beused support communications within a distributed-architecture in whichvarious components of the wearable computing system 902 are locatedremotely from one another. In this sense, the system bus 938 couldinclude elements and/or segments that support communication between suchdistributed components.

As shown, the user I/O devices 916 include a camera 918, a display 920,a speaker 922, a microphone 924, and a touchpad 926. The camera 918could correspond to the video camera 820 described in the discussion ofFIG. 8 a above. Similarly, the display 920 could correspond to an imageprocessing and display system for making images viewable to a user(wearer) of an HMD. The display 920 could include, among other elements,the first and second projectors 828 and 830 coupled with lens elements812 and 810, respectively, for generating images displays as describedin the discussion of FIG. 8 b above. The touchpad 226 could correspondto the finger-operable touch pad 824, also described in the discussionof FIG. 8 a above. The speaker 922 and microphone 924 could similarlycorrespond to components referenced in the discussion above of FIGS. 8 aand 8 b. Each of the user I/O devices 916 could also include a devicecontroller and stored, executable logic instructions, as well as aninterface for communication via the system bus 938.

The sensor devices 928, which could correspond to the sensor 822described in the discussion of FIG. 8 a, include a location sensor 930,a motion sensor 932, a magnetometer 934, and an orientation sensor 936.The location sensor 930 could correspond to a Global Positioning System(GPS) device, or other location-determination device (e.g. mobile phonesystem triangulation device, etc.). The motion sensor 932 couldcorrespond to an accelerometer or one or more gyroscopes.

The orientation sensor could include a theodolite for determining anangular orientation of a reference pointing direction of the HMD withrespect to a local terrestrial coordinate system. For instance, theorientation sensor could determine an altitude angle with respect tohorizontal and an azimuth angle with respect to geographic (or geodetic)North of a forward pointing direction of the HMD. Other angles andcoordinate systems could be used as well for determining orientation.

The magnetometer could be used to determine the strength and directionof the Earth magnetic (geomagnetic) field as measured at a currentlocation of the HMD. The magnetometer could be used as a compass,possibly in conjunction with the orientation sensor for determining theazimuth angle.

Each of the sensor devices 928 could also include a device controllerand stored, executable logic instructions, as well as an interface forcommunication via the system bus 938.

It will be appreciated that there can be numerous specificimplementations of a wearable computing system or wearable HMD, such thewearable computing system 902 illustrated in FIG. 9. Further, one ofskill in the art would understand how to devise and build such animplementation.

The present disclosure is not to be limited in terms of the particularembodiments described in this application, which are intended asillustrations of various aspects. Many modifications and variations canbe made without departing from its spirit and scope, as will be apparentto those skilled in the art. Functionally equivalent methods andapparatuses within the scope of the disclosure, in addition to thoseenumerated herein, will be apparent to those skilled in the art from theforegoing descriptions. Such modifications and variations are intendedto fall within the scope of the appended claims.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments will be apparent to those skilled in the art.The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting, with the true scopebeing indicated by the following claims, along with the full scope ofequivalents to which such claims are entitled. It is also to beunderstood that the terminology used herein is for the purpose ofdescribing particular embodiments only, and is not intended to belimiting.

1. A computer-implemented method comprising: receiving movement datafrom a plurality of sensors of a head-mounted display (HMD), wherein theplurality of sensors includes a camera, and wherein the movement datacorresponds to movement and a position of the HMD; determining that themovement data includes a data pattern corresponding to an unnaturalmovement of the HMD, wherein the unnatural movement is characteristic ofan unintentional removal of the HMD from a wearer; and in response todetermining that the movement data includes the data pattern, initiatingan action that corresponds to the unnatural movement of the HMD, whereinthe action secures the HMD.
 2. The method of claim 1, wherein theunintentional removal of the HMD comprises a physical separation betweenthe HMD and the wearer, and wherein the unintentional removal isunintended by the wearer.
 3. The method of claim 1, wherein theunnatural movement comprises a movement of the HMD that is not caused bythe wearer of the HMD.
 4. The method of claim 1, wherein initiating theaction comprises notifying authorities in response to the unintentionalremoval of the HMD corresponding to the HMD being stolen from thewearer.
 5. The method of claim 1, wherein determining that the movementdata includes a data pattern corresponding to an unnatural movement ofthe HMD comprises: determining one or more of the following movementindicators: (a) velocity of the HMD; (b) angular velocity of the HMD;and (c) acceleration of the HMD; and using the one or more movementindicators as a basis for determining that the movement data correspondsto the unnatural movement of the HMD.
 6. The method of claim 5, whereinusing the one or more movement indicators as a basis for determiningthat the movement data corresponds to the unnatural movement comprisesdetermining that each of the one or more of the movement indicatorsexceeds a respective threshold.
 7. The method of claim 5, whereininitiating the action that corresponds to the unnatural movement of theHMD comprises: determining which one of the one or more movementindicators exceeds one or more respective thresholds; and responsive todetermining the one or more respective thresholds exceeded, commencingone or more of the following operations: (a) locking the HMD, (b)disabling the HMD, and (c) sounding an alarm.
 8. A wearable-computingsystem comprising: a non-transitory computer-readable medium; programinstructions stored on the non-transitory computer-readable medium andexecutable by at least one processor to: receive movement data from aplurality of sensors of a head-mounted display (HMD), wherein theplurality of sensors includes a camera, and wherein the movement datacorresponds to an unnatural movement and an unnatural position of theHMD and wherein the unnatural movement is characteristic of anunintentional removal of the HMD from a wearer; determine that themovement data includes a data pattern that corresponds to an unnaturalmovement of the HMD; and in response to determining that the movementdata includes the data pattern, initiate an action that corresponds tothe unnatural movement of the HMD, wherein the action secures the HMD.9. The system of claim 8, wherein the plurality of sensors of the HMDcomprises at least one of: (a) an accelerometer; (b) a gyroscope; and(c) a shock sensor.
 10. The system of claim 9, wherein the plurality ofsensors of the HMD is used to determine one of the following: (a)velocity of the HMD; (b) angular velocity of the HMD; and (c)acceleration of the HMD.
 11. The system of claim 9, wherein theplurality of sensors of the HMD obtains one or more of the followingmovement indicators: (a) a direction of movement of the HMD, (b) achange in direction of the movement of the HMD, (c) an acceleration ofthe HMD; and wherein the movement indicators provide a basis todetermine that the movement data corresponds to the unnatural movementof the HMD.
 12. The system of claim 11, wherein the action thatcorresponds to the unnatural movement of the HMD causes the processorto: determine which one of the one or more movement indicators exceedsone or more respective thresholds; and responsive to the respectivethresholds exceeded, commence one or more of the following operations:(a) locking the HMD, (b) disabling the HMD, and (c) sounding an alarm.13. A computer-implemented method comprising: receiving movement datafrom a plurality of sensors of a head-mounted display (HMD), wherein theplurality of sensors includes a camera, and wherein the movement datacorresponds to movement of the HMD; determining that the movement dataincludes a data pattern characteristic of the position of the HMD andthe HMD being worn by an unauthorized user; and in response todetermining that the movement data includes the data pattern, initiatingan action that corresponds to the HMD being worn by an unauthorizeduser, wherein the action secures the HMD.
 14. The method of claim 13,wherein initiating the action comprises notifying authorities inresponse to the data pattern characteristic of the HMD being worn by theunauthorized user.
 15. The method of claim 13, wherein determining thatthe movement data includes a data pattern characteristic of the HMDbeing worn by the unauthorized user comprises: comparing the datapattern characteristic of the HMD being worn by the unauthorized userwith one or more patterns of an authorized user's natural movements; andresponsive to a mismatch between the data pattern characteristic of theHMD being worn by the unauthorized user and the one or more patterns ofthe authorized user's natural movements, initiating the action.
 16. Themethod of claim 15, wherein determining that the movement data includesthe data pattern characteristic of the HMD being worn by theunauthorized user further comprises comparing a biometric data patternof the HMD being worn by the unauthorized user with one or morebiometric data patterns of the authorized user.
 17. The method of claim16, wherein the one or more patterns of the authorized user's naturalmovements are used for providing a user-profile for the authorized user.18. The method of claim 13, wherein the plurality of sensors of the HMDcomprises at least one of: (a) an accelerometer; (b) a gyroscope; and(c) a shock sensor.
 19. The method of claim 18, wherein the plurality ofsensors of the HMD provides a basis for determining one or more of thefollowing movement indicators: (a) a direction of movement of the HMD,(b) a change in direction of the movement the HMD, and (c) a pattern ofthe movement of the HMD; and wherein the movement indicators provide abasis for determining that the movement data includes a data patterncharacteristic of the HMD being worn by an unauthorized user.
 20. Themethod of claim 19, wherein initiating the action that corresponds tothe HMD being worn by an unauthorized user comprises: determining thatthe one or more movement indicators exceeds one or more respectivethresholds indicated in a user-profile for an authorized user; andresponsive to the determining the respective thresholds exceeded,commencing one or more of the following operations: (a) locking the HMD,(b) disabling the HMD, and (c) sounding an alarm.